Avalanche Forecast

Issued: Feb 2nd, 2013 9:03AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Wind Slabs and Persistent Slabs.

triley, Avalanche Canada

South Columbia.

Summary

Confidence

Fair - Due to variable snowpack conditions for the entire period

Weather Forecast

Overnight and Sunday: Cloudy with light Westerly winds overnight becoming strong Westerly in the afternoon. No precipitation overnight, 5-10 cms Sunday afternoon. Freezing level dropping to valley bottom overnight and up to about 1000 metres during the day.Monday: Alpine temperatures -6.0 with gusty West winds and light flurries.Tuesday: Winds shifting to Southwest as the next pulse of moisture brings 5-10 cms of snow to elevations above 1000 metres.

Avalanche Summary

The cycle of natural and skier triggered avalanches continued on Friday with the average avalanche size increasing to size 2.0. The West Monashee area near Mabel Lake was the most reactive area in the region with natural avalanches up to size 3.0. There was one skier accidental avalanche size 1.5 from the Southern Selkirks that released below treeline at 1450 metres and was 40 cms deep.

Snowpack Summary

The recent storm snow has been reported to be settling into a cohesive slab above the old surfaces that were buried on January 23rd. The storm slab is about 50 cms deep in most places and is sitting on a weak layer of surface hoar and facets at treeline and below, and in some places on an old sun crust in the alpine. Some areas in the West Monashees have a layer of heavier moist snow near the surface that may be sitting on a variable freezing rain crust that is down about 20 cms.

Problems

Wind Slabs

Old wind slabs are expected to continue to be triggered by light additional loads. New wind slabs are expected to build during the next pulse of moisture.

Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Persistent Slabs

The recent storm slab has settled into a cohesive slab that can be triggered by skiers or sledders. Fractures are propagating farther and avalanche size has increased.

Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 5

Valid until: Feb 3rd, 2013 2:00PM